ABSTRACT
Objective: To investigate the effects of exosomes from human adipose-derived mesenchymal stem cells (ADSCs) on inflammatory response of mouse RAW264.7 cells and wound healing of full-thickness skin defects in mice. Methods: The experimental research methods were adopted. The discarded adipose tissue was collected from 3 female patients (aged 10-25 years) who underwent abdominal surgery in the First Affiliated Hospital of Air Force Medical University. ADSCs were extracted from the adipose tissue by collagenase Ⅰ digestion and identified with flow cytometry. Exosomes were extracted from the human ADSCs by differential ultracentrifugation, the morphology of the exosomes was observed by transmission electron microscopy, the particle diameter of the exosomes was detected by nanoparticle tracking analyzer, and the protein expressions of CD9, CD63, tumor susceptibility gene 101 (TSG101), and β-actin were detected by Western blotting. The human ADSCs exosomes (ADSCs-Exos) and RAW264.7 cells were co-cultured for 12 h, and the uptake of RAW264.7 cells for human ADSCs-Exos was observed. The RAW264.7 cells were divided into phosphate buffer solution (PBS) group stimulated with PBS for suitable time, endotoxin/lipopolysaccharide (LPS) stimulation 2 h group, LPS stimulation 4 h group, LPS stimulation 6 h group, LPS stimulation 12 h group, and LPS stimulation 24 h group stimulated with LPS for corresponding time, with 3 wells in each group, and the mRNA expressions of interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), IL-6, and IL-10 were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) method. The RAW264.7 cells were divided into PBS group, LPS alone group, and LPS+ADSCs-Exos group, with 3 wells in each group, which were dealt correspondingly for the time screened out in the previous experiment, the mRNA expressions of IL-1β, TNF-α, IL-6, IL-10, trasforming growth factor β (TGF-β,) and vascular endothelial growth factor (VEGF) were detected by real time fluorescence quantitative RT-PCR method, and the protein expressions of inducible nitric oxide synthase (iNOS) and arginase 1 (Arg1) were detected by Western blotting. Twenty-four 8-week-old male BALB/c mice were divided into PBS group and ADSCs-Exos group according to the random number table, with 12 mice in each group, and a full-thickness skin defect wound with area of 1 cm×1 cm was inflicted on the back of each mouse. Immediately after injury, the wounds of mice in the two groups were dealt correspondingly. On post injury day (PID) 1, the concentration of IL-1β and TNF-α in serum were detected by enzyme-linked immunosorbent assay, and the mRNA expressions of IL-1β, TNF-α, and IL-6 were detected by real time fluorescence quantitative RT-PCR method. On PID 3, 6, 9, 12, and 15, the wound healing was observed and the wound non-healing rate was calculated. On PID 15, the defect length of skin accessory and collagen volume fraction (CVF) were detected by hematoxylin eosin staining and Masson staining, respectively, the CD31 expression and neovascularization were detected by immunohistochemistry, and the ratio of Ki67 positive cells, the ratio of iNOS and Arg1 double positive cells, and the ratio of iNOS positive cells to Arg1 positive cells and their fluorescence intensities were detected by immunofluorescence method. The number of samples in animal experiments was 6. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and independent sample t test. Results: At 12 h of culture, the cells exhibited a typical spindle shape, which were verified as ADSCs with flow cytometry. The exosomes with a vesicular structure and particle diameters of 29-178 nm, were positively expressed CD9, CD63, and TSG101 and negatively expressed β-actin. After 12 h of co-culture, the human ADSCs-Exos were endocytosed into the cytoplasm by RAW264.7 cells. The mRNA expressions of IL-1β, TNF-α, IL-6, and IL-10 of RAW264.7 cells in LPS stimulation 2 h group, LPS stimulation 4 h group, LPS stimulation 6 h group, LPS stimulation 12 h group, and LPS stimulation 24 h group were significantly higher than those in PBS group (with t) values of 39.10, 14.55, 28.80, 4.74, 48.80, 22.97, 13.25, 36.34, 23.12, 18.71, 29.19, 41.08, 11.68, 18.06, 8.54, 43.45, 62.31, 22.52, 21.51, and 37.13, respectively, P<0.01). The stimulation 12 h with significant expressions of all the inflammatory factors was selected as the time point in the following experiment. After stimulation of 12 h, the mRNA expressions of IL-1β, TNF-α, IL-6, and IL-10 of RAW264.7 cells in LPS alone group were significantly higher than those in PBS group (with t values of 44.20, 51.26, 14.71, and 8.54, respectively, P<0.01); the mRNA expressions of IL-1β, TNF-α, and IL-6 of RAW264.7 cells in LPS+ADSCs-Exos group were significantly lower than those in LPS alone group (with t values of 22.89, 25.51, and 8.03, respectively, P<0.01), while the mRNA expressions of IL-10, TGF-β, and VEGF were significantly higher than those in LPS alone group (with t values of 9.89, 13.12, and 7.14, respectively, P<0.01). After stimulation of 12 h, the protein expression of iNOS of RAW264.7 cells in LPS alone group was significantly higher than that in PBS group and LPS+ADSCs-Exos group, respectively (with t values of 11.20 and 5.06, respectively, P<0.05 or P<0.01), and the protein expression of Arg1 was significantly lower than that in LPS+ADSCs-Exos group (t=15.01, P<0.01). On PID 1, the serum concentrations of IL-1β and TNF-α and the mRNA expressions of IL-1β, TNF-α, and IL-6 in wound tissue of mice in ADSCs-Exos group were significantly those in lower than PBS group (with t values of 15.44, 12.24, 9.24, 7.12, and 10.62, respectively, P<0.01). On PID 3, 6, 9, 12, and 15 d, the wound non-healing rates of mice in ADSCs-Exos group were (73.2±4.1)%, (53.8±3.8)%, (42.1±5.1)%, (24.1±2.8)%, and 0, which were significantly lower than (82.5±3.8)%, (71.2±4.6)%, (52.9±4.1)%, (41.5±3.6)%, and (14.8±2.5)% in PBS group, respectively (with t values of 4.77, 8.93, 5.54, 7.63, and 7.59, respectively, P<0.01). On PID 15, the defect length of skin accessory in wounds of mice in PBS group was significantly longer than that in ADSCs-Exos group (t=9.50, P<0.01), and the CVF was significantly lower than that in ADSCs-Exos group (t=9.15, P<0.01). On PID 15, the CD31 expression and the number of new blood vessels (t=12.99, P<0.01), in wound tissue of mice in ADSCs-Exos group were significantly more than those in PBS group, and the ratio of Ki67 positive cells was significantly higher than that in PBS group (t=7.52, P<0.01). On PID 15, the ratio of iNOS and Arg1 double positive cells in wound tissue of mice in PBS group was (12.33±1.97)%, which was significantly higher than (1.78±0.29)% in ADSCs-Exos group (t=13.04, P<0.01), the ratio of iNOS positive cells and the fluorescence intensity of iNOS were obviously higher than those of ADSCs-Exos group, and the ratio of Arg1 positive cells and the fluorescence intensity of Arg1 were obviously lower than those of ADSCs-Exos group. Conclusions: The human ADSCs-Exos can alleviate inflammatory response of mouse RAW264.7 cells, decrease macrophage infiltration and secretion of the pro-inflammatory cytokines, increase the secretion of anti-inflammatory cytokines to promote neovascularization and cell proliferation in full-thickness skin defect wounds of mice, hence accelerating wound healing.
Subject(s)
Animals , Female , Humans , Male , Mice , Exosomes , Mesenchymal Stem Cells , Skin , Vascular Endothelial Growth Factor A , Wound HealingABSTRACT
ObjectiveTo observe the effect of Jiangzhi Tongluo soft capsule on the protein levels of silent mating-type information regulation 2 homolog 1 （SIRT1） and forkhead transcription factor FoxO3 and podocyte apoptosis in the renal tissue of rats with membranous nephropathy and to reveal the underlying molecular mechanisms for the treatment of MN. MethodSixty male SD rats were randomly assigned into 6 groups with 10 rats each. The six groups included a normal group， a model group， benazepril hydrochloride group， and Jiangzhi Tongluo soft capsule groups of low， medium and high doses （25， 50， 100 mg·kg-1， respectively）. The model rats were established by injection with cationized bovine serum albumin into the tail vein. After modeling， the rats were administrated with corresponding agents by gavage for 4 weeks. At the end of the 4th week， an electron microscope was used to observe the pathological changes in the kidney. Western blot was employed to detect the protein levels of SIRT1 and FoxO3 protein in rat kidney， and immunohistochemistry to detect the expression of B lymphocytoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， Bcl-2-associated death promoter （Bad）， and podocyte split diaphragm proteins nephrin and podocin. ResultCompared with normal group， the expression of pro-apoptotic factors Bax， Bad， and FoxO3 in the kidney was up-regulated （P<0.05）， while that of anti-apoptotic factors Bcl-2， SIRT1， nephrin， and podocin was down-regulated （P<0.05） after modeling. Compared with the model group， the treatments down-regulated the expression of Bax， Bad， and FoxO3 （P<0.05） and up-regulated that of Bcl-2， SIRT1， nephrin， and podocin （P<0.05）. ConclusionJiangzhi Tongluo soft capsule may regulate the SIRT1/FoxO3 pathway to reduce podocyte apoptosis and maintain podocyte structure stability， thereby exerting the renal protection effect.
ABSTRACT
Objective:To investigate the intervention effect of modified Shengjiangsan on hypoxia-inducible factor-1<italic>α </italic>（HIF-1<italic>α</italic>）/nicotinamide adenine dinucleotide phosphate oxidase 4 （NOX4） signaling pathway in membranous nephropathy （MN） rats and to explore its mechanism to reduce oxidative stress and apoptosis in renal tissues. Method:Cationized bovine serum albumin （C-BSA） was injected into the tail vein of rats to replicate the MN model. Rats were randomly divided into a model group， a modified Shengjiangsan group， and a benazepril group after modeling， and administered by gavage once a day accordingly. At the end of the 4<sup>th</sup> week， the 24-h urine total protein （UTP）， urea nitrogen （BUN）， and serum creatinine （SCr） levels of each group were detected. Enzyme-linked immunosorbent assay（ELISA）was used to detect the levels of superoxide dismutase （SOD）， malondialdehyde （MDA）， and reactive oxygen species （ROS） in renal tissues of rats. In situ end labeling（TUNEL） staining was used to detect the cell apoptosis rate. The mRNA and protein expression levels of HIF-1<italic>α</italic> and NOX4 were detected by real-time fluorescence-based quantitative polymerase chain reaction（Real-time PCR）and Western blot， respectively. The immunohistochemistry method was used to detect the protein expression levels of B-cell lymphomas -2 （Bcl-2）， B-cell lymphomas xl （Bcl-xl）， Bcl-2 associated X protein （Bax）， Bcl-2 cell death regulator antibody （Bim）. Result:Compared with the normal group， the model group showed increased UTP （<italic>P</italic><0.05）， decreased SOD， elevated MDA and ROS （<italic>P</italic><0.05）， up-regulated mRNA and protein expression of HIF-1<italic>α</italic> and NOX4 （<italic>P</italic><0.05）， enhanced protein expression of Bax and Bim， declining protein expression of Bcl-xl and Bcl-2 （<italic>P</italic><0.05）， and increased cell apoptosis in renal tissues. Compared with the model group， the modified Shengjiangsan group and the benazepril group displayed declining UTP （<italic>P</italic><0.05）， up-regulated SOD， decreased MDA and ROS （<italic>P</italic><0.05）， down-regulated mRNA and protein expression of HIF-1<italic>α</italic> and NOX4 （<italic>P</italic><0.05）， diminished protein expression of Bax and Bim， elevated protein expression of Bcl-xl and Bcl-2 （<italic>P</italic><0.05）， and reduced cell apoptosis in renal tissues （<italic>P</italic><0.05）. Conclusion:The protective effect of modified Shengjiangsan on the kidney is presumedly achieved by reducing the oxidative stress and apoptosis in renal tissues of MN rats via inhibiting the HIF-1<italic>α</italic>/NOX4 signaling pathway.